1. Field of the Invention
The present invention relates to a semiconductor IC (integrated circuit) device, and particularly, to a semiconductor IC device for converting a PECL (pseudo emitter-coupled logic) signal into a TTL (transistor-transistor logic) signal.
2. Description of the Related Art
A PECL circuit employs a single power source to convert an ECL (emitter-coupled logic) signal or a PECL signal into a TTL signal. If the ground potential level of a semiconductor IC device a fluctuates due to noise, the TTL output of the device will change and this will cause following circuits to malfunction. It is necessary, therefore, to provide a semiconductor IC device capable of canceling fluctuations in a ground potential level, to thereby prevent malfunctions.